1. Field of the Invention
The present invention relates to a liquid crystal display.
2. Discussion of the Background
A liquid crystal display (LCD) is one of the most commonly used flat panel displays, and includes two substrates with electrodes formed thereon and a liquid crystal layer interposed between the two substrates. In the LCD, a voltage is applied to the electrodes to realign liquid crystal molecules of the liquid crystal layer to thereby regulate the transmittance of light passing through the liquid crystal layer.
Among LCDs, an LCD having a structure in which field generating electrodes are respectively formed on two display panels is widely used. Among the two display panels, a plurality of pixel electrodes and thin film transistors are arranged in a matrix format on one display panel (hereinafter, referred to as “a thin film transistor array panel”), and red, green, and blue color filters are formed on the other display panel with a common electrode covering the entire surface of the panel (hereinafter, referred to as “a common electrode panel”).
However, such type of LCD may lose light when passing through the polarizers and the color filters. To reduce the light loss and make a more efficient LCD, a photo-luminescent liquid crystal display (PL-LCD) has been developed to have a color conversion material instead of color filters.
The PL-LCD uses a color conversion media (CCM) instead of the color filters. In the PL-LCD device, an ultraviolet (UV) light or a bluish light that is generated from a light source and controlled by a liquid crystal layer is irradiated onto a color conversion media layer so that a visible light is generated from the color conversion media layer, thereby displaying an image. The UV light and the bluish light have relatively short wavelengths.
However, the color conversion of red and green, and a difference of the blue transmitted light may not render uniform color depending on viewing angles, which may generate the viewing angle problem. The color conversion media layer in red, green, and blue may form a step, which may cause a problem in controlling the liquid crystal.
Also, the visible lights from the fluorescent layer in various directions, and scattered by molecules in the fluorescent layer decreases luminance, resolution, and contrast ratio of the PL-LCD.